The present invention relates to torque converters for automatic transmissions in land vehicles and, more particularly, to an impeller hub, which comprises a part of the impeller assembly in such a torque converter.
The torque converter of an automatic transmission replaces the clutch used in manual transmissions. It is the primary component for transmittal of power between the engine and the transmission in an automotive vehicle. The basic principle of torque converter operation can be observed by placing the blades of two electric fans opposite each other and turning on one of the fans. If one of the fans is turned on, the force of the air column produced will act upon the motionless blades of the other fan, which will begin turning and eventually reach a speed approaching the speed of the powered fan. The torque converter employs an analogous mechanism using automatic transmission fluid (hereinafter “ATF”) to provide a fluid coupling between the engine and the transmission of an automobile, which provides for a smooth conversion of torque from the engine to the mechanical components of the transmission.
In a typical rear-wheel drive vehicle the torque converter is bolted to the engine crankshaft at its forward end so that it will rotate at engine speed. The torque converter is supported at its aft end by an impeller hub, which typically engages the hydraulic pump. Because the impeller hub projects through the transmission case and is exposed to exterior dirt and contaminants, premature wear of the mating bearing and seal can occur resulting in eventual failure of the torque converter. Thus, the present invention has been developed to resolve this problem and other shortcomings of the prior art.